Listening to scientific advice that they trust, these moms and dads fear that the cure—a potentially life-altering shot—could be worse than the disease. Many have decided to not to get their kids vaccinated—and no doubt some of those children have contracted serious illnesses and even died as a result.

Now, however, the 1998 study on which the autism-vaccine link was founded turns out to be an "elaborate fraud." According an investigation by the British medical journal BMJ, the study's author, Andrew Wakefield, lied about or changed the medical histories of all dozen patients in the study. BMJ says there is "no doubt" Wakefield is responsible.

In response to the bogus study, vaccination rates plunged 80 percent in Britain by 2004, with measles cases up dramatically. In the U.S., the Centers for Disease Control and Prevention reported more cases of measles in 2008 than in any year since 1997.

"But perhaps as important as the scare's effect on infectious disease," BMJ notes, "is the energy, emotion and money that have been diverted away from efforts to understand the real causes of autism and how to help children and families who live with it."

Wakefield apparently did it for the money. BMJ says he received $674,000 from "lawyers hoping to sue vaccine manufacturers and to create a vaccine scare."

Financial gain is hardly the only motive for science cheats. The late ­Peter B. Medawar, a Nobel Prize winner in medicine and author of the well-regarded 1990 book, The Threat and the Glory, said that simple bias is another. According to reviewer Eugenie Samuel Reich, Medawar pointed to "an unyielding belief in the truth of an untested theory."

Certainly this kind of "unyielding belief" has been on full display during the unfolding Climategate scandal. In 2009, hackers broke into the computers of the University of East Anglia, a key source of global warming data, and stole e-mails that cast a shadow over the whole theory of man-caused global warming. Several researchers related to the influential United Nations Intergovernmental Panel on Climate Change discussed deleting messages containing information that undermined the hypothesis. "This is not a smoking gun," climatologist Patrick J. Michaels said; "this is a mushroom cloud."

Further, the IPCC, red-faced, had to withdraw an assertion from a 2007 report warning that global warming would melt Himalayan glaciers by 2035. They dropped it because there was no scientific evidence for it. The scientist behind the claim, Murari Lal, admitted he made it up to put pressure on governments to do something about the climate. Talk about "an unyielding belief in the truth of an untested theory"! And they say Christians are obscurantist!

I could go on about mendacious attempts to claim cloning human beings from stem cells, create cold fusion, or do other falsehoods in the name of a supposedly impartial science. Yet the New Atheists, for example, put great stock (one might even say "faith") in the ability of science to explain everything, at least eventually.

Christopher Hitchens, author of the polemical (and largely unscientific) book God Is Not Great, says, "Physics and chemistry and biology and paleontology and archeology have, at a minimum, given us explanations for what used to be mysterious, and furnished us with hypotheses that are at least as good as, or very much better than, the ones offered by any believers in other and inexplicable dimensions." Hitchens says he is glad of this, concluding: "one desires that science and humanism would make faith obsolete."

But, the truth is, those who claim that science is "objective" and the best (or even only) path to truth are worshiping an idol that clearly has feet of clay. Those who perpetuate this kind of scientism clearly have an unscientific agenda. That is, unlike real scientists—who seek with integrity to test their hypotheses to see if they conform to the data—they are averse to any facts that contradict their secular worldview. They, indeed, "display an unyielding belief in the truth of an untested theory."

The fact is, science is not the creation of atheistic rationalism. It is rooted, and in fact flourished, in the rich soil of the Judeo-Christian worldview, in the belief that God is rational and has made an intelligible Creation to be explored and made to flourish by human beings, who are made in his image.

Sociologist and author Rodney Stark had it right when he wrote: "from early days, the church fathers taught that reason was the supreme gift from God and the means to progressively increase their understanding of scripture and revelation. Consequently, Christianity was oriented to the future, while the other major religions asserted the superiority of the past. … faith in the power of reason infused Western culture, stimulating the pursuit of science and the evolution of democratic theory and practice." So anti-Christian dogmatists such as Hitchens find themselves in the precarious position of, in their attempts to exalt reason over faith, sawing off the very branch on which they are perched.

But we also need to keep in mind that science, as valuable as it is, is a limited and (especially when misused in the service of unscientific agendas) imperfect means of acquiring knowledge. As Pope Benedict said earlier this month, some scientific theories are "mind limiting" because "they only arrive at a certain point ... and do not manage to explain the ultimate sense of reality." Because science is conducted by flawed and fallible human beings, we must accept it for what it is—a means in our epistemological endeavors, not the final word.

There are other sources of knowing that science cannot touch. Many of our universities, founded to the glory of God, have forgotten or even suppressed these sources, believing that science itself can answer any question worth asking. But philosopher Dallas Willard, reflecting on the work of quantum physicist Richard Feynman, cogently points out that "the scientific understanding of nature yields no guidance for human life, including what to do with the knowledge science offers."

Science, as good as it is, has limits. It simply cannot answer all of the questions we face, and even those it purports to answer it does so imperfectly. Science is our helper, not our ruler. To believe otherwise involves "an unyielding belief in the truth of an untested theory."